It has the jvm, zcashd, everything needed to run the wallet with a local full node of zcash baked into it. If you've already got the proving key's downloaded for use with my Mac port (source or binary release), it'll use them without re-downloading. If its a fresh, untouched Mac that's never had Zcash on it, it uses a nice GUI downloader that @zab built into the App, and pulls the proving key down via Amazon CloudFront, much faster than is typical with fetch-params.sh aka zcash-fetch-params
Please test it out, and let us know here of any issues!
Download is at: https://zcash.dl.mercerweiss.com/ZCashSwingWalletUI-1.0.3.dmg
Once we get some feedback and polish off a few little bits (LICENSE file, dmg file icon, etc) we'll be releasing a dmg signed with an Apple Developer Certificate that will install without having to have "Allow apps downloaded from: anywhere" selected in "System Preferences -> Security & Privacy"
Thanks in advance, the both of us now need to go get some sleep after pulling all nighters on this one!